import com.mysql.jdbc.Connection;

import javax.swing.text.StyledEditorKit;
import javax.xml.transform.Result;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * user:likai
 * Date:2022-12-26
 * Time:10:18
 */
//封装博客表
public class BlogDao {
    //插入一个博客到数据库（发布博客）
    public void insert(Blog blog){
        //和数据库建立连接
        Connection connection=null;
        PreparedStatement statement=null;
        try {
            connection=DBUtil.getConnection();
            String sql="insert into blog values(null,?,?,now(),?)";
            statement=connection.prepareStatement(sql);
            statement.setString(1,blog.getTitle());
            statement.setString(2,blog.getContent());
            statement.setInt(3,blog.getUserId());
            int ret=statement.executeUpdate();
            if(ret!=1){
                System.out.println("博客插入失败!");
            }else {
                System.out.println("博客插入成功!");
            }
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }finally {
            DBUtil.close(connection,statement,null);
        }
    }
    //根据博客id来查询指定的博客（博客详情页）
    public Blog selectOne(int blogId){
        Connection connection=null;
        PreparedStatement statement=null;
        ResultSet resultSet=null;
        try {
            connection=DBUtil.getConnection();
            String sql="select * from blog where blogId=?";
            statement=connection.prepareStatement(sql);
            statement.setInt(1,blogId);
            resultSet=statement.executeQuery();
            if(resultSet.next()){
                Blog blog=new Blog();
                blog.setBlogId(resultSet.getInt("blogId"));
                blog.setTitle(resultSet.getString("title"));
                blog.setContent(resultSet.getString("content"));
                blog.setPostTime(resultSet.getTimestamp("postTime"));
                blog.setUserId(resultSet.getInt("userId"));
                return blog;
            }
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }finally {
            DBUtil.close(connection,statement,resultSet);
        }
        return null;
    }
    //查询博客列表（博客列表页）
    public List<Blog> selectAll(){
        List<Blog> blogs=new ArrayList<>();
        Connection connection=null;
        PreparedStatement statement=null;
        ResultSet resultSet=null;
        try {
            connection=DBUtil.getConnection();
            String sql="select * from blog order by postTime desc";
            statement=connection.prepareStatement(sql);
            resultSet=statement.executeQuery();
            while(resultSet.next()){
                Blog blog=new Blog();
                blog.setBlogId(resultSet.getInt("blogId"));
                blog.setTitle(resultSet.getString("title"));
                String content=resultSet.getString("content");
                if(content.length()>100){
                    content=content.substring(0,100)+"...";
                }
                blog.setContent(content);
                blog.setPostTime(resultSet.getTimestamp("postTime"));
                blog.setUserId(resultSet.getInt("userId"));
                blogs.add(blog);
            }
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }finally {
            DBUtil.close(connection,statement,resultSet);
        }
        return blogs;
    }
    //删除指定的博客（删除博客）
    public void delete(int blogId){
        //和数据库建立连接
        Connection connection=null;
        PreparedStatement statement=null;
        try {
            connection=DBUtil.getConnection();
            String sql="delete from blog where blogId=?";
            statement=connection.prepareStatement(sql);
            statement.setInt(1,blogId);
            int ret=statement.executeUpdate();
            if(ret!=1){
                System.out.println("博客删除失败!");
            }else {
                System.out.println("博客删除成功!");
            }
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }finally {
            DBUtil.close(connection,statement,null);
        }
    }

}
